A conventional disk drive includes at least one rotating data storage disk and an actuator assembly for positioning a transducer head over each data storage surface of the disk or disks. The disk or disks are rotated by a spindle motor while the actuator assembly is actuated by a voice coil motor (VCM). When the disk drive loses power, for whatever reason, it is desirable to move the transducer heads to a safe landing area for parking on the disk surface or away from the disk surfaces altogether. It is well known that when a disk drive loses power, the spindle motor may act as a generator as kinetic energy from the rotational mass of the rotating disks and associated spindle may be converted into electrical energy. It is also well known that this converted electrical energy, known as back EMF (BEMF) is utilized to drive the VCM so that the transducer heads may be parked at the landing area, once power is lost. It is also desirable to bring the transducer heads to the landing area in a controlled manner, particularly when the landing area is away from the disk surface e.g. a ramp. In conventional actuator retraction systems the actual velocity of the actuator assembly is either sampled or determined over a limited range. What is needed is a more efficient system that extracts reliable full range velocity information from the VCM.